1. Field of the Invention
The present invention relates generally to a coin handling protection device and, more particularly, to a device which can be attached to a standard payphone coin handling apparatus to prevent tampering with the coin handling system.
2. Description of the Prior Art
The payphone coin handling apparatus in use today typically comprises a body having a downwardly-inclined coin chute through which coins are allowed to roll from an inlet end aligned with a coin insert slot. The body further includes a coin validator which provides a means of electronically detecting the authenticity and value of the coin as it rolls down the coin chute. The coin validator may comprise, for example, an "MS16" model coin validator manufactured by Mars Electronics. Alternatively, other types of coin validators may be used to determine the authenticity and value of coins inserted into the payphone, including those functioning mechanically or optically. Depending upon the type and value of the inserted coins and whether the telephone call is completed, the coin validator operates to selectively route the coins to a coin box or a coin return trough. A coin box chute is coupled to the outlet end of the coin chute and receives valid coins which are to be deposited in the coin box. A coin return chute is positioned adjacent to the coin validator and function to receive counterfeit coins or valid coins to be returned to the payphone customer. The coin return chute comprises a hollow body having front and back walls which are joined by opposing side walls. Each of the side walls converge at its bottom end to form a narrow throat at the exit end of the coin return chute. The coin return chute is coupled at its exit end to a coin return trough, from which a customer can retrieve coins returned from the payphone. The top of the coin return chute is open such that it may receive coins from the coin validator.
Theft of coins from payphone coin handling apparatus has been a continuing problem in payphones of the type described above. Initial forms of stuffing coin handling apparatus involved inserting compressible material, such as matchbook covers or slips of paper, through the coin insert slot and thereby lodging the compressible material in the coin chute. The compressible material caused the coin chute to fill up with coins as payphone customers unsuccessfully attempted to use the telephone. The thief retrieved these coins by pushing a coat hanger or other similar object into the coin chute and forcing the coins through an adjacent coin validator and into the coin return chute. These coins would cascade down the coin return chute and into the coin return trough where they would be retrieved by the thief.
Attempts at preventing this type of theft involved designing a coin chute that can be cleared of compressible materials. In particular, the coin chute body comprises two sidewalls pivotally connected along their top edges to a bracket through a pivot pin. Further, the coin chute sidewalls are biased together by a biasing spring positioned along their top edges. A coin release lever is pivotally connected to the exterior of the payphone unit and is coupled by a linkage to the coin chute. When the coin release lever is actuated, the coin chute sidewalls separate and release lodged coins or compressible material into the coin return chute.
While this mechanism has proved successful in preventing stuffing of the coin chute, it has given rise to yet another form of "stuffing." Rather than attempting to stuff the coin chute, thieves revert to stuffing the coin return chute. To "stuff" the coin return chute, the thief inserts compressible material through the coin insert slot and into the coin chute as described above. After the compressible material is lodged in the coin chute, the thief actuates the coin release lever, thereby depositing the compressible material into the coin return chute. Because the coin return chute converges at the exit end, the compressible material settles at the bottom of the coin return chute. The thief repeatedly deposits compressible material into the coin return chute in this manner until a sufficient amount of material collects and blocks the coin return chute exit end. After sufficient time, a sizable number of coins, which would otherwise be returned to the payphone customer, accumulates within the coin return chute behind the compressible material. The thief then pours a combustible fluid through the coin inlet slot and into the coin return chute and ignites the compressible material, thereby allowing the accumulated coins to cascade into the coin return trough for retrieval by thief. This not only means that money which should have been returned to the payphone customers is lost to the thief; but, often the coin handling apparatus is damaged by the ignited compressible material and must be repaired.
The payphone coin handling stuffing problem is an old one and until now no satisfactory solution has been found. This crime costs the phone companies enormous sums of money. Although the phone companies would not normally collect the returned money lost to the "stuffers," the phone companies incur high administrative costs in repairing the payphones and refunding the lost money to irate customers. More specifically, each phone company must employ personnel to investigate reports of payphones failing to return change, employ maintenance workers to examine and repair "stuffed" phones, and have accounting and payment systems in place to refund lost money to payphone customers. Consequently, there is a substantial need for an inexpensive device that reliably prevents stuffing which can be quickly and easily installed in an existing payphone.